diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 9ca7cb0..dd5a40c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -16,7 +16,7 @@ jobs:
     steps:
 
       - name: Checkout repo
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Setup Python
         uses: actions/setup-python@v4
@@ -80,24 +80,24 @@ jobs:
       fail-fast: false
       matrix:
         os: [ ubuntu-22.04, macos-12, windows-2022 ]
-        python: [ 3.8, 3.9, "3.10", "3.11" ]
+        python: [ 3.8, 3.9, "3.10", "3.11", "3.12" ]
     env:
       GCC_V: 11
     steps:
 
       - name: Checkout repo
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           path: modflow-devtools
       
       - name: Checkout modflow6
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           repository: MODFLOW-USGS/modflow6
           path: modflow6
       
       - name: Checkout modflow6 examples
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           repository: MODFLOW-USGS/modflow6-examples
           path: modflow6-examples
@@ -113,7 +113,6 @@ jobs:
         with:
           repository: MODFLOW-USGS/modflow6-largetestmodels
           path: modflow6-largetestmodels
-          token: ${{ github.token }}
 
       - name: Install executables
         uses: modflowpy/install-modflow-action@v1
@@ -128,10 +127,6 @@ jobs:
         uses: actions/setup-python@v4
         with:
           python-version: ${{ matrix.python }}
-          cache: 'pip'
-          cache-dependency-path: |
-            modflow-devtools/pyproject.toml
-            modflow6-examples/etc/requirements*.txt
 
       - name: Install Python packages
         working-directory: modflow-devtools
@@ -159,22 +154,19 @@ jobs:
         run: python ci_build_files.py
 
       - name: Run local tests
-        working-directory: modflow-devtools
+        working-directory: modflow-devtools/autotest
         env:
-          BIN_PATH: ~/.local/bin/modflow
           REPOS_PATH: ${{ github.workspace }}
-          GITHUB_TOKEN: ${{ github.token }}
         # use --dist loadfile to so tests requiring pytest-virtualenv run on the same worker
-        run: pytest -v -n auto --dist loadfile --durations 0 --ignore modflow_devtools/test/test_download.py
+        run: pytest -v -n auto --dist loadfile --durations 0 --ignore test_download.py
       
       - name: Run network-dependent tests
         # only invoke the GH API on one OS and Python version
         # to avoid rate limits (1000 rqs / hour / repository)
         # https://docs.github.com/en/actions/learn-github-actions/usage-limits-billing-and-administration#usage-limits
         if: runner.os == 'Linux' && matrix.python == '3.8'
-        working-directory: modflow-devtools
+        working-directory: modflow-devtools/autotest
         env:
-          BIN_PATH: ~/.local/bin/modflow
           REPOS_PATH: ${{ github.workspace }}
           GITHUB_TOKEN: ${{ github.token }}
-        run: pytest -v -n auto --durations 0 modflow_devtools/test/test_download.py
\ No newline at end of file
+        run: pytest -v -n auto --durations 0 test_download.py
\ No newline at end of file
diff --git a/.gitignore b/.gitignore
index 4ad02b9..20eb2ac 100644
--- a/.gitignore
+++ b/.gitignore
@@ -128,8 +128,9 @@ dmypy.json
 # Pyre type checker
 .pyre/
 
-# pycharme
+# IDEs
 .idea/
+.vscode/
 
 # downloaded exe
 modflow_devtools/bin/
diff --git a/DEVELOPER.md b/DEVELOPER.md
index b074df5..499e1b8 100644
--- a/DEVELOPER.md
+++ b/DEVELOPER.md
@@ -38,25 +38,21 @@ This repository's tests use [`pytest`](https://docs.pytest.org/en/latest/) and s
 
 This repository's tests expect a few environment variables:
 
-- `BIN_PATH`: path to MODFLOW 6 and related executables
 - `REPOS_PATH`: the path to MODFLOW 6 example model repositories
 - `GITHUB_TOKEN`: a GitHub authentication token
 
 These may be set manually, but the recommended approach is to configure environment variables in a `.env` file in the project root, for instance:
 
 ```
-BIN_PATH=/path/to/modflow/executables
 REPOS_PATH=/path/to/repos
 GITHUB_TOKEN=yourtoken...
 ```
 
 The tests use [`pytest-dotenv`](https://github.com/quiqua/pytest-dotenv) to detect and load variables from this file.
 
-**Note:** at minimum, the tests require that the `mf6` (or `mf6.exe` on Windows) executable is present in `BIN_PATH`.
-
 ### Running the tests
 
-Tests should be run from the project root. To run the tests in parallel with verbose output:
+Tests should be run from the `autotest` directory. To run the tests in parallel with verbose output:
 
 ```shell
 pytest -v -n auto
@@ -64,11 +60,11 @@ pytest -v -n auto
 
 ### Writing new tests
 
-Tests should follow a few conventions for ease of use and maintenance.
+Tests follow a few conventions for ease of use and maintenance.
 
 #### Temporary directories
 
-Tests which must write to disk should use `pytest`'s built-in `temp_dir` fixture or one of this package's own scoped temporary directory fixtures.
+Tests which must write to disk use `pytest`'s built-in `temp_dir` fixture or one of this package's own scoped temporary directory fixtures.
 
 ## Releasing
 
diff --git a/modflow_devtools/test/__init__.py b/autotest/__init__.py
similarity index 100%
rename from modflow_devtools/test/__init__.py
rename to autotest/__init__.py
diff --git a/conftest.py b/autotest/conftest.py
similarity index 100%
rename from conftest.py
rename to autotest/conftest.py
diff --git a/pytest.ini b/autotest/pytest.ini
similarity index 72%
rename from pytest.ini
rename to autotest/pytest.ini
index 93b6f6d..73fd077 100644
--- a/pytest.ini
+++ b/autotest/pytest.ini
@@ -4,5 +4,5 @@ python_files =
     test_*.py
     *_test*.py
 markers =
-    slow: tests that don't complete in a few seconds
+    slow: tests not completing in a few seconds
     meta: run by other tests (e.g. testing fixtures)
\ No newline at end of file
diff --git a/modflow_devtools/test/test_build.py b/autotest/test_build.py
similarity index 99%
rename from modflow_devtools/test/test_build.py
rename to autotest/test_build.py
index 3966ec0..36697f7 100644
--- a/modflow_devtools/test/test_build.py
+++ b/autotest/test_build.py
@@ -3,6 +3,7 @@
 from pathlib import Path
 
 import pytest
+
 from modflow_devtools.build import meson_build
 from modflow_devtools.markers import requires_pkg
 
diff --git a/modflow_devtools/test/test_download.py b/autotest/test_download.py
similarity index 99%
rename from modflow_devtools/test/test_download.py
rename to autotest/test_download.py
index 9fbfff7..9d5173d 100644
--- a/modflow_devtools/test/test_download.py
+++ b/autotest/test_download.py
@@ -1,5 +1,6 @@
 import pytest
 from flaky import flaky
+
 from modflow_devtools.download import (
     download_and_unzip,
     download_artifact,
diff --git a/autotest/test_executables.py b/autotest/test_executables.py
new file mode 100644
index 0000000..7d55a27
--- /dev/null
+++ b/autotest/test_executables.py
@@ -0,0 +1,26 @@
+import subprocess
+import sys
+from pathlib import Path
+from shutil import which
+
+import pytest
+
+from modflow_devtools.executables import Executables
+from modflow_devtools.misc import add_sys_path, get_suffixes
+
+ext, _ = get_suffixes(sys.platform)
+exe_stem = "pytest"
+exe_path = Path(which(exe_stem))
+bin_path = exe_path.parent
+exe = f"{exe_stem}{ext}"
+
+
+@pytest.fixture
+def exes():
+    with add_sys_path(bin_path):
+        yield Executables(**{exe_stem: bin_path / exe})
+
+
+def test_access(exes):
+    # support both attribute and dictionary style access
+    assert exes.pytest == exes["pytest"] == exe_path
diff --git a/modflow_devtools/test/test_fixtures.py b/autotest/test_fixtures.py
similarity index 97%
rename from modflow_devtools/test/test_fixtures.py
rename to autotest/test_fixtures.py
index 32d0f46..f959d0c 100644
--- a/modflow_devtools/test/test_fixtures.py
+++ b/autotest/test_fixtures.py
@@ -139,7 +139,7 @@ def test_keep_class_scoped_tmpdir(tmp_path, arg):
         TestKeepClassScopedTmpdirInner.test_keep_class_scoped_tmpdir_inner.__name__,
         "-M",
         "test_keep",
-        "-K",
+        arg,
         tmp_path,
     ]
     assert pytest.main(args) == ExitCode.OK
@@ -160,19 +160,14 @@ def test_keep_module_scoped_tmpdir(tmp_path, arg):
         test_keep_module_scoped_tmpdir_inner.__name__,
         "-M",
         "test_keep",
-        "-K",
+        arg,
         tmp_path,
     ]
     assert pytest.main(args) == ExitCode.OK
     this_path = Path(__file__)
     keep_path = (
-        tmp_path
-        / f"{str(this_path.parent.parent.name)}.{str(this_path.parent.name)}.{str(this_path.stem)}0"
+        tmp_path / f"{str(this_path.parent.name)}.{str(this_path.stem)}0"
     )
-    from pprint import pprint
-
-    print(keep_path)
-    pprint(list(keep_path.glob("*")))
     assert test_keep_fname in [f.name for f in keep_path.glob("*")]
 
 
@@ -186,7 +181,7 @@ def test_keep_session_scoped_tmpdir(tmp_path, arg, request):
         test_keep_session_scoped_tmpdir_inner.__name__,
         "-M",
         "test_keep",
-        "-K",
+        arg,
         tmp_path,
     ]
     assert pytest.main(args) == ExitCode.OK
diff --git a/autotest/test_markers.py b/autotest/test_markers.py
new file mode 100644
index 0000000..cd105c4
--- /dev/null
+++ b/autotest/test_markers.py
@@ -0,0 +1,59 @@
+from os import environ
+from platform import python_version, system
+from shutil import which
+
+from packaging.version import Version
+
+from modflow_devtools.markers import *
+
+exe = "pytest"
+
+
+@requires_exe(exe)
+def test_require_exe():
+    assert which(exe)
+    require_exe(exe)
+    require_program(exe)
+
+
+exes = [exe, "python"]
+
+
+@require_exe(*exes)
+def test_require_exe_multiple():
+    assert all(which(exe) for exe in exes)
+
+
+@requires_pkg("pytest")
+def test_requires_pkg():
+    import numpy
+
+    assert numpy is not None
+
+
+@requires_pkg("pytest", "pluggy")
+def test_requires_pkg_multiple():
+    import pluggy
+    import pytest
+
+    assert pluggy is not None and pytest is not None
+
+
+@requires_platform("Windows")
+def test_requires_platform():
+    assert system() == "Windows"
+
+
+@excludes_platform("Darwin", ci_only=True)
+def test_requires_platform_ci_only():
+    if "CI" in environ:
+        assert system() != "Darwin"
+
+
+py_ver = python_version()
+
+
+@pytest.mark.parametrize("version", ["3.12", "3.11"])
+def test_requires_python(version):
+    if Version(py_ver) >= Version(version):
+        assert requires_python(version)
diff --git a/modflow_devtools/test/test_misc.py b/autotest/test_misc.py
similarity index 90%
rename from modflow_devtools/test/test_misc.py
rename to autotest/test_misc.py
index ff4f980..7b65641 100644
--- a/modflow_devtools/test/test_misc.py
+++ b/autotest/test_misc.py
@@ -7,12 +7,13 @@
 from typing import List
 
 import pytest
-from conftest import project_root_path
+
 from modflow_devtools.misc import (
     get_model_paths,
     get_namefile_paths,
     get_packages,
     has_package,
+    has_pkg,
     set_dir,
     set_env,
     timed,
@@ -255,35 +256,9 @@ def test_get_namefile_paths_select_packages():
     assert len(paths) >= 43
 
 
-@pytest.mark.slow
-def test_has_pkg(virtualenv):
-    python = virtualenv.python
-    venv = Path(python).parent
-    pkg = "pytest"
-    dep = "pluggy"
-    print(
-        f"Using temp venv at {venv} with python {python} to test has_pkg('{pkg}') with and without '{dep}'"
-    )
-
-    # install a package and remove one of its dependencies
-    virtualenv.run(f"pip install {project_root_path}")
-    virtualenv.run(f"pip install {pkg}")
-    virtualenv.run(f"pip uninstall -y {dep}")
-
-    # check with/without strict mode
-    for strict in [False, True]:
-        cmd = (
-            f"from modflow_devtools.misc import has_pkg; print(has_pkg('{pkg}'"
-            + (", strict=True))" if strict else "))")
-        )
-        exp = "False" if strict else "True"
-        assert (
-            virtualenv.run(
-                f'{python} -c "{cmd}"',
-                capture=True,
-            ).strip()
-            == exp
-        )
+def test_has_pkg():
+    assert has_pkg("pytest")
+    assert not has_pkg("notapkg")
 
 
 def test_timed1(capfd):
diff --git a/modflow_devtools/test/test_ostags.py b/autotest/test_ostags.py
similarity index 99%
rename from modflow_devtools/test/test_ostags.py
rename to autotest/test_ostags.py
index 7ad3b91..22e93f1 100644
--- a/modflow_devtools/test/test_ostags.py
+++ b/autotest/test_ostags.py
@@ -1,6 +1,7 @@
 from platform import system
 
 import pytest
+
 from modflow_devtools.ostags import (
     OSTag,
     get_binary_suffixes,
diff --git a/modflow_devtools/test/test_zip.py b/autotest/test_zip.py
similarity index 67%
rename from modflow_devtools/test/test_zip.py
rename to autotest/test_zip.py
index b1aa28a..070b9c4 100644
--- a/modflow_devtools/test/test_zip.py
+++ b/autotest/test_zip.py
@@ -2,91 +2,73 @@
 import shutil
 import sys
 import zipfile
-from os import environ
 from pathlib import Path
 from pprint import pprint
+from shutil import which
 from zipfile import ZipFile
 
 import pytest
+
 from modflow_devtools.markers import excludes_platform
 from modflow_devtools.misc import get_suffixes, set_dir
 from modflow_devtools.zip import MFZipFile
 
-_bin_path = Path(environ.get("BIN_PATH")).expanduser().absolute()
-_ext, _ = get_suffixes(sys.platform)
-
-
-@pytest.fixture(scope="module")
-def empty_archive(module_tmpdir) -> Path:
-    # https://stackoverflow.com/a/25195628/6514033
-    data = b"PK\x05\x06\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
-    path = module_tmpdir / "empty.zip"
-
-    with open(path, "wb") as zip:
-        zip.write(data)
-
-    return path
-
-
-@pytest.fixture(scope="module")
-def nonempty_archive(module_tmpdir) -> Path:
-    if not _bin_path.is_dir():
-        pytest.skip(f"BIN_PATH ({_bin_path}) is not a directory")
-
-    zip_path = module_tmpdir / "nonempty.zip"
-    txt_path = module_tmpdir / "hw.txt"
-    exe_path = _bin_path / f"mf6{_ext}"
-
-    # create a zip file with a text file and an executable
-    shutil.copy(exe_path, module_tmpdir)
-    with open(txt_path, "w") as f:
-        f.write("hello world")
-
-    with set_dir(module_tmpdir):
-        zip = MFZipFile(zip_path.name, "w")
-        zip.write(txt_path.name, compress_type=zipfile.ZIP_DEFLATED)
-        zip.write(exe_path.name, compress_type=zipfile.ZIP_DEFLATED)
-        zip.close()
-
-    return zip_path
+ext, _ = get_suffixes(sys.platform)
+exe_stem = "pytest"
+exe_path = Path(which(exe_stem))
+exe_name = f"{exe_stem}{ext}"
 
 
 def test_compressall(function_tmpdir):
     zip_file = function_tmpdir / "output.zip"
     input_dir = function_tmpdir / "input"
     input_dir.mkdir()
-
     with open(input_dir / "data.txt", "w") as f:
         f.write("hello world")
 
     MFZipFile.compressall(str(zip_file), dir_pths=str(input_dir))
-
     pprint(list(function_tmpdir.iterdir()))
     assert zip_file.exists()
 
     output_dir = function_tmpdir / "output"
     output_dir.mkdir()
-
     ZipFile(zip_file).extractall(path=str(output_dir))
-
     pprint(list(output_dir.iterdir()))
     assert (output_dir / "data.txt").is_file()
 
 
+@pytest.fixture(scope="module")
+def empty_archive(module_tmpdir) -> Path:
+    # https://stackoverflow.com/a/25195628/6514033
+    data = b"PK\x05\x06\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+    path = module_tmpdir / "empty.zip"
+    with open(path, "wb") as zip:
+        zip.write(data)
+    yield path
+
+
 def test_extractall_empty(empty_archive, function_tmpdir):
     zf = MFZipFile(empty_archive, "r")
     zf.extractall(str(function_tmpdir))
-
     assert not any(function_tmpdir.iterdir())
 
 
+@pytest.fixture(scope="module")
+def archive(module_tmpdir) -> Path:
+    zip_path = module_tmpdir / "nonempty.zip"
+    shutil.copy(exe_path, module_tmpdir)
+    with set_dir(module_tmpdir):
+        zip = MFZipFile(zip_path.name, "w")
+        zip.write(exe_path.name, compress_type=zipfile.ZIP_DEFLATED)
+        zip.close()
+    yield zip_path
+
+
 @pytest.mark.parametrize("mf", [True, False])
 @excludes_platform("Windows")
-def test_preserves_execute_permission(function_tmpdir, nonempty_archive, mf):
-    zip = MFZipFile(nonempty_archive) if mf else ZipFile(nonempty_archive)
+def test_extractall_preserves_execute_permission(function_tmpdir, archive, mf):
+    zip = MFZipFile(archive) if mf else ZipFile(archive)
     zip.extractall(path=str(function_tmpdir))
-
-    exe_path = function_tmpdir / f"mf6{_ext}"
-
-    assert exe_path.is_file()
-    assert os.access(exe_path, os.X_OK) == mf
+    path = function_tmpdir / exe_name
+    assert path.is_file()
+    assert os.access(path, os.X_OK) == mf
diff --git a/docs/md/executables.md b/docs/md/executables.md
index d235cc5..cfc8d79 100644
--- a/docs/md/executables.md
+++ b/docs/md/executables.md
@@ -29,14 +29,3 @@ def test_targets(targets):
     # attribute- and dictionary-style access is supported
     assert targets["mf6"] == targets.mf6
 ```
-
-There is also a convenience function for getting a program's version string. The function will automatically strip the program name from the output (assumed delimited with `:`).
-
-```python
-import subprocess
-
-def test_executables_version(targets):
-    # returns e.g. '6.4.1 Release 12/09/2022'
-    assert targets.get_version(targets.mf6) == \  
-           subprocess.check_output([f"{targets.mf6}", "-v"]).decode('utf-8').strip().split(":")[1].strip()
-```
diff --git a/docs/md/markers.md b/docs/md/markers.md
index bd9714c..a50aec3 100644
--- a/docs/md/markers.md
+++ b/docs/md/markers.md
@@ -78,4 +78,11 @@ Both these markers accept a `ci_only` flag, which indicates whether the policy s
 Markers are also provided to ping network resources and skip if unavailable:
 
 - `@requires_github`: skips if `github.com` is unreachable
-- `@requires_spatial_reference`: skips if `spatialreference.org` is unreachable
\ No newline at end of file
+- `@requires_spatial_reference`: skips if `spatialreference.org` is unreachable
+
+## Aliases
+
+All markers are aliased to imperative mood, e.g. `require_github`. Some have other aliases as well:
+
+`requires_pkg` -> `require[s]_package`
+`requires_exe` -> `require[s]_program`
diff --git a/modflow_devtools/download.py b/modflow_devtools/download.py
index 3741f05..fcf045b 100644
--- a/modflow_devtools/download.py
+++ b/modflow_devtools/download.py
@@ -87,7 +87,7 @@ def get_response_json():
                     return json.loads(resp.read().decode())
             except urllib.error.HTTPError as err:
                 if err.code == 401 and os.environ.get("GITHUB_TOKEN"):
-                    raise ValueError("GITHUB_TOKEN env is invalid") from err
+                    raise ValueError("GITHUB_TOKEN is invalid") from err
                 elif err.code == 403 and "rate limit exceeded" in err.reason:
                     raise ValueError(
                         f"use GITHUB_TOKEN env to bypass rate limit ({err})"
diff --git a/modflow_devtools/executables.py b/modflow_devtools/executables.py
index 28c966d..9ec0370 100644
--- a/modflow_devtools/executables.py
+++ b/modflow_devtools/executables.py
@@ -1,10 +1,6 @@
-import sys
-from os import PathLike
 from pathlib import Path
 from types import SimpleNamespace
-from typing import Dict, Optional
-
-from modflow_devtools.misc import get_suffixes, run_cmd
+from typing import Dict
 
 
 class Executables(SimpleNamespace):
@@ -27,14 +23,3 @@ def as_dict(self) -> Dict[str, Path]:
         """
 
         return self.__dict__.copy()
-
-    @staticmethod
-    def get_version(path: PathLike = None, flag: str = "-v") -> Optional[str]:
-        """Get an executable's version string."""
-
-        out, err, ret = run_cmd(str(path), flag)
-        if ret == 0:
-            out = "".join(out).strip()
-            return out.split(":")[1].strip()
-        else:
-            return None
diff --git a/modflow_devtools/markers.py b/modflow_devtools/markers.py
index d40ca5c..1c21e43 100644
--- a/modflow_devtools/markers.py
+++ b/modflow_devtools/markers.py
@@ -1,4 +1,11 @@
-from platform import system
+"""
+Pytest markers to toggle tests based on environment conditions.
+Occasionally useful to directly assert environment expectations.
+"""
+
+from platform import python_version, system
+
+from packaging.version import Version
 
 from modflow_devtools.imports import import_optional_dependency
 from modflow_devtools.misc import (
@@ -10,6 +17,7 @@
 )
 
 pytest = import_optional_dependency("pytest")
+py_ver = Version(python_version())
 
 
 def requires_exe(*exes):
@@ -21,6 +29,23 @@ def requires_exe(*exes):
     )
 
 
+def requires_python(version, bound="lower"):
+    if not isinstance(version, str):
+        raise ValueError(f"Version must a string")
+
+    py_tgt = Version(version)
+    if bound == "lower":
+        return py_ver >= py_tgt
+    elif bound == "upper":
+        return py_ver <= py_tgt
+    elif bound == "exact":
+        return py_ver == py_tgt
+    else:
+        return ValueError(
+            f"Invalid bound type: {bound} (use 'upper', 'lower', or 'exact')"
+        )
+
+
 def requires_pkg(*pkgs):
     missing = {pkg for pkg in pkgs if not has_pkg(pkg, strict=True)}
     return pytest.mark.skipif(
@@ -69,3 +94,20 @@ def excludes_branch(branch):
     not is_connected("spatialreference.org"),
     reason="spatialreference.org is required.",
 )
+
+
+# imperative mood renaming, and some aliases
+
+require_exe = requires_exe
+require_program = requires_exe
+requires_program = requires_exe
+require_python = requires_python
+require_pkg = requires_pkg
+require_package = requires_pkg
+requires_package = requires_pkg
+require_platform = requires_platform
+exclude_platform = excludes_platform
+require_branch = requires_branch
+exclude_branch = excludes_branch
+require_github = requires_github
+require_spatial_reference = requires_spatial_reference
diff --git a/modflow_devtools/misc.py b/modflow_devtools/misc.py
index 9646aee..4915d8c 100644
--- a/modflow_devtools/misc.py
+++ b/modflow_devtools/misc.py
@@ -66,8 +66,9 @@ def set_env(*remove, **update):
 
 class add_sys_path:
     """
-    Context manager for temporarily editing the system path
-    (https://stackoverflow.com/a/39855753/6514033)
+    Context manager to add temporarily to the system path.
+
+    Adapted from https://stackoverflow.com/a/39855753/6514033.
     """
 
     def __init__(self, path):
diff --git a/modflow_devtools/test/test_executables.py b/modflow_devtools/test/test_executables.py
deleted file mode 100644
index 483103a..0000000
--- a/modflow_devtools/test/test_executables.py
+++ /dev/null
@@ -1,44 +0,0 @@
-import subprocess
-import sys
-from os import environ
-from pathlib import Path
-
-import pytest
-from modflow_devtools.executables import Executables
-from modflow_devtools.misc import add_sys_path, get_suffixes
-
-_bin_path = Path(environ.get("BIN_PATH")).expanduser().absolute()
-_ext, _ = get_suffixes(sys.platform)
-
-
-@pytest.fixture
-def exes():
-    if not _bin_path.is_dir():
-        pytest.skip(f"BIN_PATH ({_bin_path}) is not a directory")
-
-    with add_sys_path(str(_bin_path)):
-        yield Executables(
-            **{
-                "mf6": _bin_path / f"mf6{_ext}",
-            }
-        )
-
-
-def test_get_version(exes):
-    ver_str = Executables.get_version(exes.mf6)
-    version = (
-        subprocess.check_output([f"{exes.mf6}", "-v"])
-        .decode("utf-8")
-        .split(":")[1]
-        .strip()
-    )
-    assert ver_str == version
-    assert int(ver_str[0].split(".")[0]) >= 6
-
-
-def test_mapping(exes):
-    print(exes.mf6)
-    assert (
-        exes.mf6 == exes["mf6"]
-    )  # should support both attribute and dictionary access
-    assert exes.mf6 == _bin_path / f"mf6{_ext}"  # should be the correct path
diff --git a/modflow_devtools/test/test_markers.py b/modflow_devtools/test/test_markers.py
deleted file mode 100644
index 95f497c..0000000
--- a/modflow_devtools/test/test_markers.py
+++ /dev/null
@@ -1,49 +0,0 @@
-from os import environ
-from platform import system
-from shutil import which
-
-from modflow_devtools.markers import (
-    excludes_platform,
-    requires_exe,
-    requires_pkg,
-    requires_platform,
-)
-
-
-@requires_exe("mf6")
-def test_requires_exe():
-    assert which("mf6")
-
-
-exes = ["mfusg", "mfnwt"]
-
-
-@requires_exe(*exes)
-def test_requires_exe_multiple():
-    assert all(which(exe) for exe in exes)
-
-
-@requires_pkg("numpy")
-def test_requires_pkg():
-    import numpy
-
-    assert numpy is not None
-
-
-@requires_pkg("numpy", "matplotlib")
-def test_requires_pkg_multiple():
-    import matplotlib
-    import numpy
-
-    assert numpy is not None and matplotlib is not None
-
-
-@requires_platform("Windows")
-def test_requires_platform():
-    assert system() == "Windows"
-
-
-@excludes_platform("Darwin", ci_only=True)
-def test_requires_platform_ci_only():
-    if "CI" in environ:
-        assert system() != "Darwin"
diff --git a/pyproject.toml b/pyproject.toml
index c3630b7..4d2a701 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -10,6 +10,9 @@ name = "modflow-devtools"
 description = "Python tools for MODFLOW development"
 authors = [
     {name = "Joseph D. Hughes", email = "modflow@usgs.gov"},
+    {name = "Michael Reno", email = "mreno@ucar.edu"},
+    {name = "Mike Taves", email = "mwtoews@gmail.com"},
+    {name = "Wes Bonelli", email = "wbonelli@ucar.edu"},
 ]
 maintainers = [
     {name = "Joseph D. Hughes", email = "modflow@usgs.gov"},
@@ -33,6 +36,7 @@ classifiers = [
     "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
+    "Programming Language :: Python :: 3.12",
     "Topic :: Scientific/Engineering :: Hydrology"
 ]
 requires-python = ">=3.8"
@@ -58,7 +62,6 @@ test = [
     "pytest-cases",
     "pytest-cov",
     "pytest-dotenv",
-    "pytest-virtualenv",
     "pytest-xdist",
     "PyYaml"
 ]
@@ -84,10 +87,11 @@ verbose = true
 
 [tool.isort]
 profile = "black"
-src_paths = ["src/modflow_devtools"]
+src_paths = ["modflow_devtools"]
 line_length = 79
 
 [tool.setuptools]
+packages = ["modflow_devtools"]
 include-package-data = true
 zip-safe = false